Various types of mechanical depilatory devices have been proposed and are known in the marketplace.
In applicants' U.S. Pat. No. 4,524,772 there is described an electrically powered depilatory device including a hand held portable housing, motor apparatus disposed in the housing, and a helical spring comprising a plurality of adjacent windings arranged to be driven by the motor apparatus in rotational sliding motion relative to the skin bearing hair to be removed, the helical spring including an arcuate hair engaging portion arranged to define a convex side whereat the windings are spread apart and a concave side corresponding thereto whereat the windings are pressed together, the rotational motion of the helical spring producing continuous motion of the windings from a spread apart orientation at the convex side to a pressed together orientation at the concave side for engagement and plucking of hair from the skin, whereby the surface velocities of the windings relative to the hair greatly exceed the surface velocity of the housing relative thereto.
The above-described device has met with very considerable commercial success throughout the world. The Background of the Invention section of U.S. Pat. No. 4,524,772 describes the most relevant prior art relative thereto including, U.S. Pat. Nos. 1,232,617; 1,743,590; 2,458,911; 2,486,616; 2,900,661 and 4,079,741 and Swiss Pat. Nos. 179,261 and 268,696.